8286562: GCC 12 reports some compiler warnings

[zzambers]

Backport fixes few warnings in newer gcc (12+), which I have seen some when doing test build for gcc15 (fedora 42) for another backport. Warning do not show in current GHA runs because it uses gcc 10. (Btw this change has also been backported to oracle jdk 11.)

Backport is not clear, there were some differences in surrounding context, copyright headers, location of gmk file etc. So part of it had to be done manually. Changes to jfrTraceIdBits.inline.hpp are not present, because modified function is not present on jdk11.

I also included backport of followup change (JDK-8293691), which fixes problem introduced by original backported change.

GHA tests: OK

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Progress

• [ ] Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• [ ] JDK-8293691 needs maintainer approval
• [x] Change must not contain extraneous whitespace
• [ ] JDK-8286562 needs maintainer approval
• [x] Commit message must refer to an issue

Warning

 ⚠️ Found leading lowercase letter in issue title for 8293691: converting a defined BasicType value to a string should not crash the VM

Issues

• JDK-8286562: GCC 12 reports some compiler warnings (Bug - P4)
• JDK-8293691: converting a defined BasicType value to a string should not crash the VM (Bug - P4)

Reviewing

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